In order to improve the performance of organic electronic (OE) devices, such as organic field effect transistors (OFETs) or organic light emitting diodes (OLEDs), it is desirable to be able to deposit, from a solution, the individual functional layers, for example the semiconductor layer, in a specific, confined place on a substrate.
Bank structures, and methods of forming them, are known to be used for defining such confined places on a substrate. For example, US 2007/0023837 A1, WO 2008/117395 A1, EP 1 933 393 A1, GB 2,458,454 A, GB 2,462,845 A, US 2003/017360 A1, US 2007/190673 A1, WO 2007/023272 A1 and WO 2009/077738 A1 individually and collectively are representative disclosures of such known structures and methods. However, despite these disclosures, none provide a manufacturing process or material that is compatible with ink-jet printing or photolithography, or that discloses a solution processable material that is useable without harmful reactive or migrating chemicals or methods.
Thus it would be desirable to provide structure defining materials for use in forming bank structures that are compatible with ink-jet printing or photolithography which are essentially free of the aforementioned harmful reactive or migrating chemicals. Additionally it would be desirable to provide methods of forming such bank structures using methods that are both compatible with ink-jet printing or photolithography and do not require the use of processes such as halocarbon reactive ion etching. Still further it would be desirable to provide OE devices manufactured using such desirable structure defining materials and structure forming methods.